Transesterification Reaction Research Articles

Application of Catalysts Used in Biodiesel Production - A Review

Biodiesel stands as a promising alternative to traditional fossil fuels for transportation, boasting renewability, biodegradability, and environmental friendliness. However, the efficiency of biodiesel production hinges on the catalytic processes that expedite the crucial transesterification reaction between triglycerides and alcohols. The choice of catalyst becomes a multifaceted decision, influenced by factors such as feedstock quality, specific reaction conditions, and the environmental footprint associated with the catalyst itself. This comprehensive paper deals the current state of catalysts employed in biodiesel production, offering readers a nuanced understanding of the subject. The catalyst landscape is explored through an intricate analysis of various types, encompassing homogeneous, heterogeneous, enzymatic, nano, and bio-derived catalysts. A critical component of the paper is the exploration of recent advancements in catalyst synthesis techniques. This includes an assessment of the performance of these novel catalysts, elucidating their potential contributions to enhancing the biodiesel production process. By offering insights into the future prospects of these catalysts within the context of biodiesel production, the paper contributes to the evolving discourse on sustainable energy sources. In pursuit of its overarching goal, the paper aspires to furnish readers with more than just an up-to-date overview; it aims to provide a thorough examination of the prevailing trends and challenges in the realm of catalyst utilization for biodiesel production. As the world seeks greener alternatives, this paper offers valuable insights that extend beyond the present, fostering a deeper understanding of the dynamics shaping the future of biodiesel production and sustainable transportation.

Heteropolyacid and Lithium Infused Calcium Oxide Catalyst for Biodiesel Production from Food Waste

The advancement of mixed metal oxide catalysts has attracted considerable attention among various workers. Supported MoOx catalyst materials possess more Lewis and Brønsted acid functionalities which assist in the efficient biodiesel production. In this study, ammonium molybdate and Li+ were loaded over eggshells-derived calcium oxide to transesterify the frying oil/waste cooking oil (WCO) to produce biodiesel/fatty acid methyl ester (FAME). Characterization techniques i.e., X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis were employed to confirm the material. The surface modelling predicted the transesterification reaction parameters. The optimal condition to transesterify WCO with synthesized Mo/Li/CaO catalyst was 6 wt.% catalyst dose, 13.70:1 ratio of methanol:oil (m/o), time of 1 h and 60 ºC temperature. The optimum FAME yield of 97% was observed. The gas chromatography-mass spectroscopy (GC-MS) and other spectroscopic techniques were used to analyze produced FAME. The reusability of catalyst was good and the catalyst can be reutilized effectively up to a limit of 5 runs. By leveraging this innovative catalyst derived from eggshells, this study contribute to a more sustainable and cost-effective biodiesel production process.

Transesterifikasi In Situ Minyak Biji Pepaya Menggunakan Ko-pelarut Tetrahidrofuran: Pengaruh Waktu Reaksi dan Penggunaan Katalis Natrium Hidroksida

The papaya seed oil is a non-food oil that can be used as raw material for biodiesel. The transesterification process using oil as raw material requires long process stages so it is not efficient. In situ transesterification with a co-solvent is an alternative to overcome this problem. This research aims to obtain optimum conditions for the in situ transesterification reaction of papaya seed oil with THF co-solvent. The research operating conditions included stirring speed 450 rpm, reaction at room temperature, oil:methanol molar ratio = 1:101.39, catalyst:oil molar ratio = 0.5:1, oil:THF molar ratio = 1: 67.85, reaction time are 3, 8, 13, 18, 23, 28 minutes and reactions with and without a NaOH catalyst. The best research conditions were obtained in the in situ transesterification reaction of papaya seed oil with THF co-solvent using a NaOH catalyst at a reaction time of 33 minutes, producing a crude yield of 74.38% and methyl esters concentration of 98,036.4 ppm and physical properties of biodiesel that met SNI 7182-2015, namely density 0.89 g/mL and acid number 0.44 mg KOH/g sample.

Colloidal Characteristics of Poly(L-Lactic Acid)-b-Poly (ε-Caprolactone) Block Copolymer-Based Nanoparticles Obtained by an Emulsification/Evaporation Method.

Poly(L-lactic acid) (PLLA) and poly(ε-caprolactone) (PCL), two biodegradable and biocompatible polymers that are commonly used for biomedical applications, are, respectively, the result of the ring-opening polymerization of LA and ε-CL, cyclic esters, which can be produced according to several mechanisms (cationic, monomer-activated cationic, anionic, and coordination-insertion), except for L-lactide, which is polymerized only by anionic, cationic, or coordination-insertion polymerization. A series of well-defined PLLA-b-PCL block copolymers have been obtained starting from the same PLLA homopolymer, having a molar mass of 2500 g·mol-1, and being synthesized by coordination-insertion in the presence of tin octoate. PCL blocks were obtained via a cationic-activated monomer mechanism to limit transesterification reactions, and their molar masses varied from 1800 to 18,500 g·mol-1. The physicochemical properties of the copolymers were determined by 1H NMR, SEC, and DSC. Moreover, a series of nanoparticles (NPs) were prepared starting from these polyester-based copolymers by an emulsification/evaporation method. The sizes of the obtained NPs varied between 140 and 150 nm, as a function of the molar mass of the copolymers. Monomodal distribution curves with PDI values under 0.1 were obtained by Dynamic Light Scattering (DLS) and their spherical shape was confirmed by TEM. The increase in the temperature from 25 to 37 °C induced only a very slight decrease in the NP sizes. The results obtained in this preliminary study indicate that NPs have a temperature stability, allowing us to consider their use as drug-loaded nanocarriers for biomedical applications.

Spontaneous acetyl group migration between xylose and arabinose in arabinoxylan-derived oligosaccharide

Previously, a synthetic β-1,4-xylooligosaccharide having the non-reducing-end xylopyranosyl residue both acetylated and arabinosylated was reported to undergo an acetyl group migration [Bella et al., 2023]. This process was further investigated in this work by NMR spectroscopy. It was found that the spontaneous transesterification reaction was regioselective involving the acetyl group transfer from position O-2 of the xylopyranosyl residue exclusively to position O-2 of the α-l-arabinofuranosyl moiety linked to position 3 of the same xylose. Finally, the acetyl group migration resulted in an equilibrium, where the arabinose 2-acetate predominated over the xylose 2-acetate. This is the first report of acetyl group migration between different pentoses, which are in addition, glycosidically interconnected. This intramolecular transacetylation may have significant consequences on the structure of acetylated fragments generated in arabinoxylan hydrolyzates. In turn, it can broaden enzyme repertoire related to biotechnological exploitation of the esterified arabinoxylan fragments, e.g., through its enzyme-catalyzed deesterification of 2-acetylated arabinose moiety.

Experimental and computational investigations of biodiesel production from castor oil using Li-doped salmon fish bone-supported lanthanum oxide catalyst in a micro-reactor

Ensuring efficient and sustainable biodiesel production is essential for addressing environmental concerns and meeting global energy demands. This study aims to optimize the transesterification of castor oil through the development of a distinctive Li-doped-salmon fish bone (SFB)-supported La2O3 composite catalyst within a micro-reactor setup. The optimal catalyst (3 % Li/SFB-La) was thoroughly evaluated for its physicochemical features employing a range of characterization techniques, including XRD, XPS, BET, FESEM, TEM, TGA/DSC, and FT-IR. According to density functional theory (DFT) calculations, the function of Li dopants, which have a lower electronegativity (0.98) compared to La (1.1), is to enhance the charge transfer capability of La sites, thereby increasing their reactivity with triglycerides. In the interim, we determined the optimized reaction conditions: a 6:1 methanol/oil molar ratio and a 5 wt % catalyst loading at 338 K. Under these parameters, an impressive 99.38 % conversion was achieved within 1.5 h. Furthermore, the 3 % Li/SFB-La composite catalyst exhibited remarkable stability, retaining its high activity throughout 7 cycles without any significant loss of efficacy. Moreover, the transesterification reaction kinetics were thoroughly investigated, revealing a reaction rate constant of 1.17 h−1 and an activation energy of 14.46 kJ/mol.

Valorization of Glycerol to Glycerol Carbonate and Glycidol by Different Dialkyl Carbonates Utilizing Tricalcium Aluminate Hexahydrate as Transesterification Catalyst

AbstractIn this study, we report a base‐catalyzed transesterification reaction of glycerol, a waste product of the biodiesel industry, with various dialkyl carbonates, which act both as reactants and solvents, to convert glycerol carbonate into an industrially useful molecular building block. The catalyst, being used for the first time, is also a waste product from industry, present in bauxite residues and in the Portland cement, simply known as tricalcium aluminate. Despite being well‐known and readily available, this solid is only extremely poorly researched catalyst, nevertheless, using dimethyl and diethyl carbonate, glycerol conversion rates >80% and glycerol carbonate yields >60% could be achieved in just 1 h (under air atmosphere and reflux). In a comparison of the performance with other catalysts commonly researched today, as well as with other components of red mud and cements, the results showed that tricalcium aluminate is excellent, cheap, and largely environmentally friendly material for this purpose. Reusability studies of the catalysts have also shown that they provide high conversion and product yields even after repeated use, although different material characterization techniques showed intense glycerol‐catalyst surface interaction and intermediate product formation, the deactivating side effects of which could be avoided by catalyst regeneration steps.

Kinetic and optimization study of ultrasound-assisted biodiesel production from waste coconut scum oil using porous CoFe2O4@sulfonated graphene oxide magnetic nanocatalysts: CI engine approach

In this study, CoFe2O4@sulfonated graphene oxide (SGO) heterogeneous nanocatalyst was synthesized and utilized to produce biodiesel from waste coconut scum oil (WCSO). The structural features of CoFe2O4@SGO nanocatalyst were evaluated by SEM, TEM, EDX, FTIR, XRD, CO2/TPD, VSM, and BET analyses. According to these analyses, CoFe2O4@SGO nanocatalyst has high specific surface area, suitable functional groups, and good reactivity. The highest biodiesel yield using CoFe2O4@SGO nanocatalyst in optimal conditions (MeOH/WCSO ratio = 12.41, temperature = 64.73 °C, catalyst concentration = 2.24 %, and ultrasonic time = 33.08 min) was 96.87 %. The yield of biodiesel decreased from 96.91 % to 90.17 % after six reuse cycles, which demonstrates the significant stability of CoFe2O4@SGO nanocatalyst in the transesterification process. After 7 reuse steps, XRD and CO2/TPD analyzes revealed that the catalytic activity and crystallinity of the nanocatalyst were almost retained. The kinetic behavior of biodiesel generation showed that the transesterification reaction is endothermic. Enhancing the concentration of biodiesel in the fuel mix had a positive impact on the reduction of CO and UHC emissions, as well as diesel engine parameters such as cylinder pressure, BP, EGT, BSFC, and BTE. Owing to the high biodiesel yield, significant reusability, and positive impacts on the diesel engine, CoFe2O4@SGO nanocatalyst is recommended for industrial applications.

Manipulate dynamic chemical interactions in renewable polymers for 3D printing tunable, healable, and recyclable metamaterials

Mechanical metamaterials have garnered significant interests due to their unique properties, which arise from the periodic structures of their constituent units. However, traditional mechanical metamaterials suffer from limitations of fixed properties of the constituent units or irreversibility if they are damaged or little-to-no recyclability. Addressing this challenge, herein, a photoresin consisting of a monomer synthesized from a renewable biomass—epoxidized soybean oil (ESO)—citric acid (CA) and other components was developed for light-based 3D printing. It is discovered that the UV irradiation initiates photopolymerized of the highly photoactive epoxidized soybean oil-ethyl acrylamide (ESO-EA) monomer while enabling the epoxy-acid reaction (EAR) of the epoxy groups in ESO-EA with carboxyl groups in CA to create dynamic chemical bonds (DCBs). This formed dynamic crosslinking network endows the printed material with tunable tensile strengths (0.3–10.4 MPa) and shape memory behaviors (transition temperature: 22–48 °C) while maintaining high stretchability (fractural strain: 81 %–205 %). Thermal annealing facilitates dynamic transesterification reactions (DTER) to further improve the mechanical properties while making the printed materials healable and recyclable. By integrating these innovations into liquid crystal display (LCD) based 3D printing, we demonstrate origami metamaterials with tunable, multi-stable mechanical behaviors as well as property recovery after self-healing of the damaged structures by both simulations and experiments. Finally, the printed metamaterials can be recycled with the well-preserved properties.

Reaction of β‐Ketoester and 1,3‐Diol to Access Chemically Recyclable and Mechanically Robust Poly(vinyl alcohol) Thermosets through Incorporation of β‐(1,3‐dioxane)ester

AbstractThe development of mechanically robust, chemically stable, and yet recyclable polymers represents an essential undertaking in the context of advancing a circular economy for plastics. Here, we introduce a novel cleavable β‐(1,3‐dioxane)ester (DXE) linkage, synthesized through the catalyst‐free reaction of β‐ketoester and 1,3‐diol, to cross‐link poly(vinyl alcohol) (PVA) for the formation of high‐performance thermosets with inherent chemical recyclability. PVA, modified with β‐ketoester groups through the transesterification reaction with excess tert‐butyl acetoacetate, undergoes cross‐linking reactions with the unmodified 1,3‐diols within PVA itself upon thermal treatment. The cross‐linking architecture improves PVA’s mechanical properties, with Young's modulus and toughness that can reach up to 656 MPa and 84 MJ cm−3, i.e. approximately 3‐ and 12‐fold those of linear PVA, respectively. Thermal treatment of the cross‐linked PVA polymers under acid conditions leads to deconstruction of the networks, enabling the excellent recovery (>90 %) of PVA. In the absence of either thermal or acidic treatment, the cross‐linked PVA maintains its dimensional stability. We show that the recovery of PVA is also possible when the treatment is performed in the presence of other plastics commonly found in recycling mixtures. Furthermore, PVA‐based composites comprising carbon fibers and activated charcoal cross‐linked by the DXE linkages are also shown to be recyclable with recovery of the PVA and the fillers.

Thermal activation of basic oxygen furnace slag as a heterogeneous catalyst in transesterification: Characterization and catalytic activity studies

The valorization of industrial by-products has garnered significant attention in recent years due to its potential to enhance sustainability and economic efficiency within various sectors. Basic Oxygen Furnace slag (BOF-S), a by-product generated in the steelmaking process characterized by its complex composition, presents an opportunity for waste management and resource recovery. This study investigates the potential of BOF-S as a catalyst in converting waste cooking oil to biodiesel via the transesterification reaction. To improve its efficiency, BOF-S was calcined at 850 °C (BOF-S 850), and 1000 °C (BOF-S 1000), for 5 h. The BOF-S was characterized using XRF, N2 sorption, XRD, TGA-DSC, SEM-EDS and FTIR. The characterization techniques showed that the BOF-S 850 had superior characteristics as a catalyst: rough surface, increased pore size and more active basic sites compared to the BOF-S and the BOF-S 1000 slag samples. The transesterification reaction was conducted at a methanol: oil ratio of 20:1, a catalyst loading of 20 wt %, a reaction time of 12 h, a reaction temperature of 60 °C, and a stirring speed of 750 rpm. The findings established that the BOF-S 850 was the best catalyst, with a 90.77 % biodiesel yield and was able to sustain a maximum of two transesterification cycle runs.

Box-Behnken design (BBD) for optimization and simulation of biolubricant production from biomass using aspen plus with techno-economic analysis

The growing concern and limitations for existing lubricants have driven the need for biolubricants, extensively proposed as the most suitable and sustainable lubricating oils. Biolubricant refers to lubricants that quickly biodegrade and are non-toxic to humans and aquatic habitats. Over the last decade, there has been a significant increase in the production of biolubricants due to the rising demand for replacing petroleum-based lubricants with those derived from renewable sources like vegetable oils and lipase that are used in various applications. In this study biodiesel (FAME) produced from blending animal fats and waste cooking was used as a raw material with ethylene glycol for biolubricant production using a transesterification reaction in the presence of calcium oxide which considers the newest and novel part as there is no production of biolubricant from animal fats and waste cooking oil in previous researches. The reaction parameters of biolubricant production were optimized using response surface methodology (RSM) with the aid of Box Behnken Design (BBD) to study the effect of independent variables on the yield of biolubricant. These variables are temperature ranging from (100–150 °C), reaction time ranging from 1 to 4 h, and FAME (Fatty Acid Methyl Ester) to alcohol molar ratio ranging from (2:1) to (4:1). The highest biolubricant yield is 91.56% at a temperature of 141 °C, a FAME/alcohol molar ratio of 2:1, and 3.3 h. Various analyses were performed on the produced biolubricant at the optimum conditions. The results include a pour point of -9 °C, a flash point of 192 °C, a kinematic viscosity at 40 °C of 10.35 cSt, a viscosity index of 183.6, an ash content of 0.76 wt.%, and a carbon residue of 1.5 wt.%, comparing favorably with the ISO VG 10 standard. The production process of biolubricant was simulated with Aspen Plus version 11 using a Non-Random Two-Liquid (NRTL) fluid package. The simulation results indicated that the production process can be applied on an industrial scale. Economic analysis was performed on the biolubricants production plant. The total capital investment was $12.7 M with a payback period of 1.48 years and an internal rate of return (IRR) of 67.5% indicating the suitability and profitability of the biolubricant production.

Investigation into the Fuel Characteristics of Biodiesel Synthesized through the Transesterification of Palm Oil Using a TiO2/CH3ONa Nanocatalyst

Biodiesel is a renewable and sustainable alternative fuel to petrol-derived diesel. Decreasing the operating costs by improving the catalyst’s characteristics is an effective way to increase the competitiveness of biodiesel in the fuel market. An aqueous solution of sodium methoxide (CH3ONa), which is a traditional alkaline catalyst, was immersed in nanometer-sized particles of titanium dioxide (TiO2) powder to prepare the strong alkaline catalyst TiO2/CH3ONa. The immersion method was used to enhance the transesterification reaction. The mixture of TiO2 and CH3ONa was calcined in a high-temperature furnace in a range between 150 and 450 °C continuously for 4 h. The heterogeneous alkaline catalyst TiO2/CH3ONa was then used to catalyze the strong alkaline transesterification reaction of palm oil with methanol. The highest content of fatty acid methyl esters (FAMEs), which amounted to 95.9%, was produced when the molar ratio of methanol to palm oil was equal to 6, and 3 wt.% TiO2/CH3ONa was used, based on the weight of the palm oil. The FAMEs produced from the above conditions were also found to have the lowest kinematic viscosity of 4.17 mm2/s, an acid value of 0.32 mg KOH/g oil, and a water content of 0.031 wt.%, as well as the highest heating value of 40.02 MJ/kg and cetane index of 50.05. The lower catalyst amount of 1 wt.%, in contrast, resulted in the lowest cetane index of 49.31. The highest distillation temperature of 355 °C was found when 3 wt.% of the catalyst was added to the reactant mixture with a methanol/palm oil molar ratio of 6. The prepared catalyst is considered effective for improving the fuel characteristics of biodiesel.

Thermochemical valorisation of cattle manure into gaseous fuel and furfural-rich bio-oil

Surplus carbon, in the form of carbon dioxide (CO2), has aggravated global warming over several past decades. To divert the current energy mix that relies heavily on fossil fuels, researchers have realised waste materials as alternative energy. Such attempts could reduce CO2 emissions and potentially contribute to establishing a circular economy. This study investigated the transformation of cattle manure (CM) into value-added products (syngas and furfural) via a thermochemical pathway. The CM was treated with FeCl3 prior to pyrolysis to enhance the conversion selectivity toward syngas and furfural. Slow-pyrolysis was conducted to determine the mechanisms of syngas production, and fast-pyrolysis was undertaken to optimize bio-oil production. Thermogravimetric analysis revealed that Fe impregnation facilitated the thermal degradation of CM, resulting in enhanced syngas formation. The oil product obtained from the Fe-impregnated CM exhibited notable enrichment in furfural and a much simpler chemical composition than that of the untreated CM. Furthermore, the produced biochar catalytically expedited the kinetics of the transesterification reaction of canola oil. The overall results of this study offer a practical means of converting livestock manure into useful resources, thereby contributing to the realisation of a circular economy.

Modular Synthesis of Azines Bearing a Guanidine Core from N-Heterocyclic Carbene (NHC)-Derived Selenoureas and Diazo Reagents.

N-Heterocyclic carbene (NHC)-derived selenoureas comprise a fundamentally important class of NHC derivatives, with key applications in coordination chemistry and the determination of NHC electronic properties. Considering the broad reactivity of chalcogen-containing compounds, it is surprising to note that the use of NHC-derived selenoureas as organic synthons remains essentially unexplored. The present contribution introduces a novel, straightforward transformation leading to azines bearing a guanidine moiety, through the reaction of a wide range of NHC-derived selenoureas with commercially available diazo compounds, in the presence of triphenylphosphine. This transformation offers a new approach to such products, having biological, materials chemistry, and organic synthesis applications. The guanidine-bearing azines are obtained in excellent yields, with all manipulations taking place in air. A reaction mechanism is proposed, based on both experimental mechanistic findings and density functional theory (DFT) calculations. A one-pot, multicomponent transesterification reaction between selenoureas, α-diazoesters, alcohols, and triphenylphosphine was also developed, providing highly functionalized azines.

Application of LaNi1-xCoxO3 perovskite structure catalyst for conversion of waste vegetable cooking oil to biodiesel

The catalytic activity of the lanthanum nickelate (LaNiO3; LNO) and cobalt-doped lanthanum nickel oxide (LaNi1-xCoxO3; LN1-xCxO) as Ni-based perovskite structures for the waste vegetable cooking oil (WVCO) conversion to biodiesel was assessed. The phase purity and structural identity of the synthesized samples LNO and LN1-xCxO were verified by BET, NH3/CO2-TPD, SEM-EDX, ICP-OES, XRD, and TEM. From analyzing the characterization of catalysts, it is evident that doping LNO with cobalt, in addition to increasing the catalyst's surface area, by the formation of oxygen vacancies in the perovskite structure caused the improvement of the catalytic activity by providing more active sites during the WVCO transesterification reaction. According to the analysis of the data obtained from the optimization of the WVCO transesterification reaction via response surface methodology (RSM) based on the central composite design (CCD), the use of the LN0.8C0.2O catalyst resulted in the WVCO conversion of 97.28 % to biodiesel.

Synthesis and Characterization of Biodiesel from Non-Edible Seed Oils Extracted from Cameroon Bioresources

This work aimed at valorizing non-edible seed oils from some plants found in Cameroon videlicet Acacia hockii (AH), Garcinia livingstonei (GL) and Moringa oleifera (MO), through production of biodiesel. Two extraction methods used were; the Soxhlet extraction and surfactant assisted extraction with sodium dodecyl sulphate (SDS) as surfactant. The extracted oils were characterized using physicochemical parameters. The characterized oils were used to synthesize biodiesels via acid and base catalyzed transesterification reactions. The purification of the biodiesels was done using chromatographic columns. The biodiesels obtained were also characterized using physicochemical analysis in a manner similar to the oils with additional parameters like cold f low properties, f lammability, ignition qualities and cetane number determinations. Qualitative analysis was realized using the Fourier Transformed Infrared Spectrophotometer (FT-IR). The Soxhlet extraction method gave higher yields for all the plants with MO being the highest, compared to the surfactant assisted extractions. The results from the physicochemical properties of the oils were as follows: specific gravity, 0.876 g/mL, 0.843 g/mL and 0.865 g/mL for AH, GL, and MO. The free fatty acid contents of the oils were 0.436% FFA, 0.547% FFA and 1.60% FFA for AH, GL, and MO respectively. The saponification values gave 143.03 mgKOH/g, 72.93 mgKOH/g, 126.22 mgKOH/g for AH, GL and MO in that order. Iodine values for the oils were 46.54 mgI2/g, 22.41 mgI2/g, 68.10 mgI2/g for AH, GL, and MO, respectively. The peroxide values gave 10.05 meq/kg, 8.50 meq/kg, 8.0 meq/kg for AH, GL, and MO, respectively. The kinematic viscosities were 21.0 mm2/s, 22.0 mm2/s and 43.0 mm2/s for AH, GL, and MO, respectively. The acid catalyzed reaction gave greater crude yields of 90.00% for all three plants while the base catalyzed reaction gave, 87.00% (AH), 84.00% (GL) and 74.00% (MO). The purified biodiesel samples had the following acid numbers: 0.028% FFA for BAH, 0.022% FFA for BGL, and 0.028% FFA for BMO. The kinematic viscosities values for biodiesel were 4.00 mm2/s, 4.23 mm2/s, and 5.22 mm2/s for BAH, BGL, and BMO, respectively. The cetane numbers of the synthesized biodiesel samples were 142.73 (BAH), 167.29 (BGL), and 82.40 (BMO). The IR spectra of the biodiesels corroborated the chemical make-up of biodiesel. Hence non-edible seed oils from the Cameroon rich bioresources can be valorized in biodiesel synthesis and other forms of green energy production in Cameroon and beyond.

Sustainable Biodiesel Production via Biogenic Catalyzed Transesterification of Baobab Oil Methyl Ester and Optimization Process

Biomass diesel is one of the sustainable and renewable sources of energy envisaged to hold a prominent position in the world energy infrastructure. In this study, biodiesel was production from baobab seed oil by transesterification using biogenic heterogeneous catalyst, derived from mixed wastes of white chicken eggshells and banana fruit peels. The production process was analyzed and statistically analyzed using Box-Behnken Design-Response Surface Methodology (BBD-RSM). The influential transesterification reaction parameters investigated with their ranges include reaction time (40–80 min), molar ratio of oil to methanol (1:9–1:15) and catalyst weight (3–5 wt%). The nano-catalyst (CaO-BFP-850 NPs) was prepared by calcination at high temperature of 850 °C for 4 h, and its properties were found to contain majorly the basic elements of Ca and K when investigated with analytical instruments such as SEM, EDS, DSC-TGA, FT-IR, and XRD. The regeneration test of the CaO-BFP-850 NPs conducted showed it could be reused for more than four cycles with less catalytic efficiency reduction. The ideal conditions instituted by BBD-RSM was 75 min of reaction time, 12.8:1 molar ratio of oil to methanol, and 4.08 wt% CaO-BFP-850 at 65 °C and 650 rpm constant temperature and agitation speed respectively, with the validated biodiesel yield of 96.70 wt%. The assessment of the quality of the biodiesel produced showed compliance with the standard specifications of ASTM D6751, EN 14241, and SANS 833.

β-Cyclodextrin and APTES functionalized magnetic iron oxide nanoparticles for improved lipase immobilization, transesterification efficiency, and reusability

This study focuses on the immobilization of Rhizopus oryzae lipase (ROL) on magnetic iron oxide nanoparticles (MNPs) through physical adsorption, taking advantage of the magnetic properties of the nanoparticles for easy separation. Different types of nano-biocatalysts were prepared by immobilizing the lipase enzyme on bare iron nanoparticles (Fe3O4), APTES-functionalized iron nanoparticles (Fe3O4-APTES), and β-cyclodextrin-functionalized iron nanoparticles (Fe3O4-APTES-GA-β_CD). These nano-biocatalysts were employed in the transesterification process. The synthesis of Fe3O4 nanoparticles was achieved using the coprecipitation method, and the structural, magnetic, and morphological properties of the iron nanoparticles (MNPs) were characterized through FTIR, XRD, VSM, SEM, and TEM analyses. The presence of strong physical bonds, resulting from hydrophilic and hydrophobic adsorption between β-cyclodextrin and the enzyme, led to an increased loading amount from 27.37% to 44.89%. The nano-biocatalysts exhibited enhanced thermal and storage stability compared to free lipase. In transesterification reactions, ROL/Fe3O4-APTES-GA-β_CD exhibited the highest conversion percentage of 64.3% among the functionalized enzymes. Furthermore, the reusability study demonstrated that ROL/Fe3O4-APTES-GA-β_CD retained 40.9% of the initial conversion percentage after five cycles, displaying the highest reusability among all nano-biocatalysts in this study.

Resolution of Glycerol, Ethanol and Methanol Employing a Voltammetric Electronic Tongue

This paper reports the use of nanoparticles (NPs)-modified voltammetric sensors for the rapid determination of glycerol in the presence of ethanol and methanol, which are used in the transesterification reaction of biodiesel production. Two different modified electrodes have been prepared to form the electronic tongue (ET): copper hexacyanoferrate NPs obtained by chemical synthesis and mixed into graphite/epoxy (GEC) electrode, and nickel hydroxide NPs electrodeposited in reduced graphene oxide onto a GEC electrode. The response characteristics of these electrodes were first evaluated by building the respective calibration against glycerol, ethanol, and methanol. The electrodes demonstrated good stability during their analytical characterization, while principal component analysis confirmed the differentiated response against the different alcohols. Finally, the quantification of mixtures of these substances was achieved by a genetic algorithm-artificial neural networks (GA-ANNs) model, showing satisfactory agreement between expected and obtained values.